Canada



lll

lll)

dll

lill

li li METHI) FOR 'TR-:EATING NITER CAKE.

zlieieii.

Speeicatlon of Letters Pahrrt.

Patented Sept.. 9, 11u19m Appleatiozn filed October 7, 1918. Serial No. 257;245.

To all fui/tom, it meg] (foncer/ii lle it known that I, #lamme Revisionen, a euhjeet ol' the 'King oit (lrreat Britain, and a reeideut el. Uhetham, eouuty of, Northumberland, Province of llew llrtuiewielr, Dominiou of Cauadzu hare invented certain new and useful luiproveniente iii Methode for Treating Mitel- Calm, oit which the follow rug is a lull and eleair epi-ieilieatioo.

' lhe ohjeet ol thie. invention ie to ]irorirle a method ol. obtainloor 'valuable vproduote tites aud hieullitee oi lime, Iuagueeia or soda o lor wood-pulp inami'faoturo and for other puroosee.

Niteeealre a byproduct ol? the manulaeture of nitric aeid and eousislie of an acid eodiuu'i eullato oil the oheiuieal ilorotiula hlal-lfhllO,M or ol.E a neutral eoduuu Sulfate euro taining a large peroeritage `olf` illree eulfurie acid. llVheo this ailier-relie is heated with ourhori to decomposition temperature, the

Said aoid sodium .Cial-tate orfree acid is decomposed or Split up into eullur dioxuh ei'irhouie dioirid aud watern aeeordiug to tlui iollowiitglr chemical equation, vm;

lllhe gases thus evolved, pase olf, leaving he hind a more or lees neutral sodiui'n Sulfate, in accordance with the completeness of the chemical reaction.

la order to carry lout my invention in :auraulaeturire.,r practice, l grind to a line powder aud thoroughly mit: together niter oake and Vegetable carbon, preferably wood charcoal, iu the proportion of' one hundred parte ol oitooealre to `live or six parte oli charcoal and heat the mixture 11i a specially eouatrueted rouille furnace mauitained at e temperature of from 500 to 14:00 degreee of lead' pipes immersed in Cold water in or der to cool them to about the temperature ot the atmosphere; and, secondly, through an absorption `reusel or tower, huilt of sheet lead and lilled loosely "with illeciti-resisting material sueh as hard hurried eolie, lump quartz, or hard burned eartheuwaro briolror tiles, the said material being kept moist with water, in order that the said moistened loro i terial will aheorh and remove-trom theoaeelug gases; the Sulfur trioxid; and, thirdly9 vthrough a "vessel or reeeele containing' au oxygeaeoutaining compound oli a metal oli' the alkalis oralkaliue earths as weak milla; of lime or milk of magueeia, either separately or as aimiirture of hoth. (lime and magnesia), or through an aqueous solution of an alkali euehee sodiumearhonate or hy droxid, whereby the eulllur dioaid ie ah-I Sor-bed and separated from the eurhonie acid and anyeir with which the @ase-e from the furnaeeare mixed. The sull-"ur dioxid ferme a eulite or'hisullte with the mill: of linie, maguesia or alkali, n e the oaee may he lu lieu of mill: el lime, outdoor-lia or au aqueiiue solution oil' eodiuiu carhoiiato or hydrruddy `the cooler rasee from the luruaee may he corri/eyed into a tower or lou containing; liu'iestoue kept moist with a downpllow ol water; or, iu pleee el? auoh lower or towrure9 he sucked 'with the aid oli a Vacuum appara#V tue through a body ol lump limestone immersed in water and contained in vessels con v structed of wood or other aeid-resisting ma teriale, the object in hoth oaeee heilig to sepm :irate the eultt'ur dioxid hy absorption from the Carbon dioXid and to form a eul'ite or loi eullite of lime suitable for the rnaoufaeture ol'i wood-pulp by what ie loiowii as the eul fito procese, or lor other purjjioeee The particular form of ffluruaee l employ :lor deeouipoeiuoj the aeid sodium sulfate or the treo sullurie acid iu the hitter-cake ie -huilt olf lire-hriek materiale and is showin iu llll llll

lili

ldll

lll)

` the carbonio acid takes place.

when in the milie of the furnace, should be opening into the inutile, to enable the oper.- atorror workman to throw the charge or mixture of niter-cake and charcoal or vegetable carbon into the muiiie and to Withdraw. the more or less neutral sulfate when thel chemical action between the niterlcarke and charcoal has ceased or nearly so. Instead. of charging the furnaceV with the mixture through the doors,I find it advantageous to do so through earthenware pi es in the arches from Ahoppers placed a ove these pipes. I also find it advanta eous toidivide the hearth b in the muie Nbythe crosswalls e into tivo or more sections, so that a portion of' 4the mixture of niter-cake and carbon can be placed in each section at in-1 tervals to insure a more uniformv disengagement of sulfur dioxid and other gases.

Three pipes p are in each section and con nected together on the outside as shown are vprovided to take away the sulfur dioxid, 'carbonic acid and water, all more or less mixed with air, to the cooler, purifier and absorbing apparatus above described ,Where the separation ofthe sulfur dioxid from The mixture',

stirred with a rake to promote the dec0niposition of the acid sulfate or free sulfuric acid and the draft from the interior ofthe y mule M regulated to prevent the gases which are heavier than air from escaping through the doors d.`

Any suitable apparatus may be em loyed for stirring the mixture in the mu e I prefer the mechanism illustrated, which consists mainlyr of a rake or stirrer d mounted in each of the colnpartments and aliixed to the lower end of a vertical shaft o extending up through the flue B and provided with a worm-gear `e at its upper end.` The three Worm-gears are operated in unison by means of Worms f alixed to a horizontal shaft g j ournaled on top ofthe furnace and errang to be driven in any suitable manner.

The nature and scopepfthe invention having been thus indicated and its preferred embodiment having been specifically described, what is claimed as new is:

1. The method, Whlch comprises heating niter-cake in a substantially non-oxidizing atmosphere with carbonaceous material at a temperature sulicient to convert the acid sulfate content of the cake into normal sulfate and decompose any sulfuric acid present, and converting the sulfur trioxid content ofthe gases into sulfuric acid and reactingwith vthe remaining sulfur dioxid content on substances capable of forming. therewith com` mercial Sultesl p Y 2. The method, which comprises heating niter-cake in a Inutile furnace with carbonat a temperature suflicient to convert `the 'acid content of the cake into normal sulfate'a'nd to decomposeany free acid, an'd subjecting` the gases first to absorption in Water-to form acid 4and then to alkali metal compound containing oxygen and capable of forming a sulte. e

AIn testimony whereof I hereunto afiix my signature. Y

' v JAMES BEVERTDQF, 

